1. Field of the Invention
The invention is related to an active device array substrate, and in particular to an active device array substrate which has a copper conductive layer.
2. Description of Related Art
As panel sizes of thin film transistor liquid crystal displays (TFT-LCD) become larger and larger, this enlargement is accompanied by resistor capacitor (RC) delay effects caused by resistance values of metal wires which are not low enough. Signals are hence distorted during transmission, thereby affecting the display quality of the panels. By using a single layer of copper which has low resistance as a metal wire, RC delay effects are effectively reduced. However, after the copper is fabricated, copper oxide is formed on the surface of the copper. Since the rates at which the copper oxide on the surface of the copper and the copper are etched are different, disconnection of wires may easily occur during etching.